Question

Sally is 4 years older than Tim. Together, the sum of their ages is 20. How old is each person?

Answer 1

Tim is `8` and Sally is `12`.

Explanation:

You can represent each person's age using variables. Let `x` = Tim's age. Because Sally is 4 years older than Tim, you can represent her age as `4 + x`.

Sally's Age = `4 + x`
Tim's Age = `x`

The sum of their ages is `20`, so add both expressions.

`(4+x) + (x) = 20`.
`4 + 2x = 20`
`2x = 16`
`x = 8`

`x` represents Tim's age, so Tim is `8`. Sally is `4` years older, so Sally is `12`.